As President of the Metropolitan Swimming Federation in Brazil, Havelange became a member of the Brazilian Olympic Committee and joined the International Cycling Union in 1958. After becoming Vice-President of the Brazilian Sports Confederation, he served as President of the Confederation from 1958 to 1973.[6]

In 1974, Havelange defeated Englishman Stanley Rous for the presidency of FIFA, the governing body of world association football. Havelange became the first non-European to hold the post. He lobbied in 86 different countries for the presidency, often accompanied by Pelé.[7] Sports marketer Patrick Nally said that "Havelange had seen the future...he knew that if he became the president of the only federation already running its own high-profile world championship then he would enjoy huge economic power".[8] Appealing to developing nations, Havelange promised an expanded World Cup, and a youth World Cup that they might be able to host.[7]

Threatened by Havelange's international campaign for the presidency, Rous asked Horst Dassler, then managing Adidas' French subsidiary to help his campaign.[8] Dassler engaged in intense lobbying of the delegates at the 39th FIFA Congress, where the vote was to be held. The election went to a second round, and Havelange won by sixteen votes.[8]

Havelange did not have sufficient money to fund his programme for FIFA, so he sought financial support from Dassler, who wished to supply Adidas branded equipment to the national federations.[8] Supported by sports marketer Patrick Nally, Havelange enlisted Adidas and Coca-Cola as primary sponsors of FIFA tournaments. The two companies also underwrote the expenses of FIFA tournaments, with Coca-Cola underwriting the 1978 FIFA World Cup in Argentina for $8 million.

The support of commercial organizations was crucial to the future of Havelange and FIFA, and provided a model for global sporting federations. Nally stated that "The money we bought into FIFA through Coke was clearly changing the face of the federation. Havelange was building a new international headquarters in Zurich, appointing professional full-time staff and PR and finance people. FIFA was showing the way. Other federations were watching closely. Many others were eager to follow and quick to fall into the hands of Horst and myself"[8] The triumvirate of João Havelange, Horst Dassler and Patrick Nally would have profound effects on the future of world sport.

The sale of television rights increased greatly under Havelange's leadership. In 1987 the European rights to the next three FIFA World Cups were sold for $440 million, the non-United States rights for the three tournaments from 1998 sold for $2.2 billion.[9] Under Havelange's presidency the FIFA World Cup expanded from 16 to 32 teams, with Havelange overseeing six world cups during his time in office.[10] The FIFA U-17 World Cup, FIFA U-20 World Cup, FIFA Confederations Cup and FIFA Women's World Cup were all introduced under his tenure.[10]

Havelange was also an associate of Brazilian criminal Castor de Andrade, head of an illegal gambling association.[12] Andrade was sentenced to six years in prison in 1994 for racketeering. Havelange wrote a character reference for Andrade in 1987, as "amiable and pleasant .. predominant feature .. loyalty .. good family man, a devoted friend, and is admired as a sports administrator".[13] "I authorize Castor de Andrade to use this statement as he deems appropriate".[12] Police investigating Andrade found this reference and evidence that Andrade had provided Havelange with a box at the Rio Carnival.[12]

João Havelange's daughter, Lucia, was married to the Brazilian football administrator Ricardo Teixeira for 30 years. They divorced in 1997.[10] Teixeira was President of the Brazilian Football Confederation (CBF) between 1989 and 2012. A financier, Teixeira had no previous experience of sports administration.[14]

In 1993, angry when his television company was rejected in a contest for domestic rights,[15] Brazilian footballer Pelé accused Teixeira of corruption, resulting in an eight year feud between Pelé and Havelange.[14] Consequently, Havelange banned Pelé from the draw for the 1994 FIFA World Cup in Las Vegas. Criticisms over the ban were perceived to have negatively affected Havelange's chances of re-election as FIFA President in 1994.[15] As in 1974 Havelange embarked on an intense lobbying mission, with the aim of securing votes from the Confederation of African Football (CAF), Asian Football Confederation (AFC) and the Central American, North American and Caribbean Football Confederation (CONCACAF). The loyalty of these "third world" football federations was rewarded by the expansion of the World Cup from 24 to 32 teams for the 1998 FIFA World Cup. As a result of the expansion and allocation of places, tension grew between the governing body of European football (UEFA) and the FIFA leadership.

As Brazilian Minister for Sports, Pelé drafted legislation approved to Pelé Law in December 1997 by the lower house of the Brazilian congress. Football clubs had to become companies within two years, giving players greater freedom of contract and limiting the power of the Brazilian Football Confederation. Havelange threatened to ban Brazil from the 1998 FIFA World Cup if the law passed.[16]

At the 1994 meeting of the FIFA Executive Committee in New York, Havelange was criticized for his allocation of appointments to FIFA's standing committees. Havelange postponed a discussion on the appointments, distributed a list with the new composition of the committees, and declared the list passed without a vote.[15]

Johansson said "The dumbest thing about breaking the agreement is that we're faced with an expensive competition. We would be better off spending the money on real soccer." Johansson criticized Havelange's financial decisions and "undemocratic behaviour."[17] At a meeting of the FIFA Executive Committee, Johansson demanded Sepp Blatter resign as FIFA General Secretary if he planned to run for the presidency of FIFA. Havelange rejected the demand and ended the meeting before a vote could be taken, described as "a defeat for democracy" by Johansson.[17] If elected, Johansson planned that an independent accountant would examine FIFA's business practices under Havelange.[17] Blatter was elected by 111 to 80 votes, amid claims of bribery.[18]

In 1999, De Telegraaf reported that Havelange accepted gifts of diamonds, bicycles, sports articles, Delft blue porcelain, paintings and art books, in connection with Amsterdam's failed bid for the 1992 Summer Olympic Games.[19] "I remember it very well because he had special wishes, wishes which were in conflict with the IOC laws," said Peter Kronenberg, who headed the press office of the Amsterdam Olympic Games 1992 Foundation.[19]

Disagreements between Nally and Dassler led to the foundation of International Sport and Leisure (ISL) in 1982. Dassler, French businessman Andre Guelfi, and Japanese advertising firm Dentsu established ISL to help market the rights for the 1986 FIFA World Cup in Mexico. Dassler's proximity to Havelange, and his support for Juan Antonio Samaranch, the Presidents of the International Olympic Committee (IOC) enabled ISL to win lucrative future World Cup and Olympic contracts. Following Dassler's death in 1987, and the departure of key executives, ISL overpaid for sports rights in the 1990s, and was declared bankrupt in 2001. From 1989 to 2001, ISL paid 185 million Swiss francs (CHF) in "personal commissions" to sports officials and other people involved in the marketing of sports rights. In the 2008 fraud trial that arose from the collapse of ISL, a judge referred to the commissions as "schmiergeld", a German word for bribery.

In May 2006, British investigative reporter Andrew Jennings' book Foul! The Secret World of FIFA: Bribes, Vote-Rigging and Ticket Scandals implicated Havelange in the collapse of ISL, and revealed that some football officials were urged to secretly repay the commissions they received.[20] In 2011, Jennings told Brazil's Senate that Havelange may have amassed $50 million or more in bribes, through a front company called Sicuretta.[21]

A IOC ethics committee was announced in June 2011, to investigate claims that Havelange received a bribe of $1 million in connection with ISL.[22] The investigation was prompted by the Jennings's claims in FIFA's Shame, an episode of Panorama broadcast on BBC One in May 2011.[22] Days before the ethics committee was set to happen, Havelange resigned as a member of the IOC, citing health concerns. The investigation was closed, with reports that it would have suspended the membership of Havelange for two years.[23] In November 2011, Jennings accused Havelange of being one of the people who collectively paid 5.5 million CHF to close the 2008 ISL fraud trial.[24]

In July 2012 after protracted court proceedings, Havelange and Teixeira were named as beneficiaries of bribes from ISL. A prosecutor in the canton of Zug revealed a document saying that, from 1992 to 2000, Havelange and Teixeira were paid 41m CHF by ISL.[25] Teixeira had resigned from FIFA in March 2012.[26]

At the time of this payment, commercial bribery was not a crime in Switzerland.[25] In 1997, as President of FIFA, Havelange had granted ISL FIFA's exclusive marketing rights, and exclusive TV and radio rights to the 2002 and 2006 World Cups in 1998. ISL paid FIFA 200m CHF for the marketing rights and $1.4 billion for the TV rights. After ISL's bankruptcy, its liquidators examined all payments made by the company.[25]

FIFA, under the presidency of Sepp Blatter, was found to have known about the bribes, yet argued it did not need to have the money repaid. Prosecutions were mounted for alleged embezzlement against Havelange and Teixeira, but were stopped in May 2010, after Havelange and Texeira repaid CHF500,000 and CHF2.5m respectively.[25] The repayments were considered reasonable, because bribes paid before 1995 were outside the statute of limitations, and Havelange was now over 90 years old.[25]

The prosecutor also believed that Havelange and Teixeira were guilty of criminal breaches of their duties to serve FIFA as senior executives.[25] Following the release of the report, Blatter vowed to strip Havelange of his honorary presidency at the next FIFA Congress.[27]

In March and April 2012, Havelange was hospitalized for a seriously infected right ankle in Rio de Janeiro, which necessitated a period in intensive care.[28][29][30] In April 2013 he resigned from his position as FIFA's Honorary President, for "health and personal reasons".[3] Havelange was again admitted to hospital in June 2014, for a lung infection.[31]

Havelange has a Bachelor in Law from the Law School of Niterói (Fluminense Federal University). At 24, he acquired a doctorate in Law.[32] He worked as a lawyer for bus company Auto Viação Jabaquara, and is president-director of another, Viação Cometa S/A.[32] He is also senior partner at Orwec Química e Metalurgia Ltda.[32][33]

He was elected honorary president of FIFA in 1998,[2] but resigned in 2013.[3] On August 24, 2006 Havelange was named honorary Vice President of the Brazilian Ice Sports Federation (CBDG) for his support in the development of winter sports in Brazil.[34]